Plastic bowling pin with metal core



July 25, 1967 N. J. HALlP 3,332,685

PLASTIC BOWLING PIN WITH METAL CORE Filed March 19, 1964 United States Patent O lice 3,332,685 PLASTIC BOWLING PIN WITH METAL CORE Nicholas Joseph Halip, 1907 Arras St., Windsor, Ontari Canada Filed Mar. 19, 1964, Ser. No. 354,818 (Filed under Rule 47(b) and 35 U.S.C. 118) 11 Claims. (Cl. 273-82) This invention relates to bowling pins. More particularly, this invention relates to bowling pins made of plastic which, while possessing a number of the advantages of conventional wooden bowling pins, avoid a number of the more significant disadvantages thereof.

A primary disadvantage of conventional wooden bowling pins is that they may, and often do, vary in weight significantly on account of the non-uniform density of the wood from which they are made. Thus, in order to obtain a set of wooden bowling pins which are even relatively closely matched in weight, it is necessary to manu- Ifacture considerably more wooden bowling pins than are necessary for one complete set and to choose bowling pins from these that are yas closely matched in weight as possible. This process of selection and matching is time consuming and adds to the cost of conventional wooden bowling pins. Moreover, the set of bowling pins which is obtained often is not a perfectly matched set, and a pin of this set may vary significantly in weight with respect to pins from other sets, which also is an undesirable feature.

Accordingly, one object of my invention is to provide plastic bowling pins which may be made of uniform weight and which do not require subsequent selection and matching.

Another disadvantage of conventional wooden bowling pins is that in normal use they should be replaced at least every year. In many cases more frequent replace- -ment is required. Furthermore, the plastic coating, which is employed on conventional wooden bowling pins for the purpose of protecting the wood, flakes and chips after the pins have been in use for only a matter of weeks. Consequently, such pins require frequent resurfacing.

l Accordingly, another object of my invention is to provide plastic bowling pins which will last several times as long as conventional bowling pins Aand which will require only infrequent resurfacing.

Experience has shown that conventional wooden bowling pins tend lto fracture at the heads thereof, because the head is the thinnest and hence weakest part of a wooden bowling pin.

Accordingly, it is yet another object of my invention to provide a plastic bowling pin with a metal core, such a bowling pin having an exceptionally strong head.

It is well known that mechanical pin setters subject conventional wooden bowling pins to wear and cause abrasion and chipping of such pins.

Accordingly, another object of my invention is to provide a plastic bowlingvpin better able to withstand the abuse of mechanical pin setters.

The source of raw material for wooden bowling pins is limited, and manufacturers of such pins often find it necessary to purchase whole forests well in advance. A forest fire in these forests might well slow down for several years production of wooden bowling pins by the owners of the forests. Furthermore, suitable supplies of wood generally are not available near large manufacturing centers. Consequently, either the wood must be transported to the bowling pin manufacturer, or the manufacturer must locate near his source of raw material. Both of these alternatives create a number of economic problems.

Yet a further object of my invention is to provide bowling pins made of a material which is readily available in large manufacturing centers.

3,332,685 Patented July 25, 1967 In the production of wooden bowling pins the following steps are required: kiln drying, squaring, turning, smoothing, coating with filler, lacquering and dipping in plastic. Many of these steps require considerable time, and, in a number of cases, considerable time must elapse between steps.

It is a further object of my invention to provide plastic bowling pins which can be made quickly by a simple injection molding process which avoids all of the aforementioned steps.

lAn additional and important object of my invention is to provide plastic bowling pins which simulate the sound of wood when struck and which are capable of creating the same action as wooden bowling pins.

In brief, a bowling pin embodying my vinvention has plastic side walls which define lan interior compartment. A plurality of divider walls divide the interior compartment into a plurality of smaller compartments, the divider walls forming -a rigid web supporting the side walls.

My invention will become more apparent from the f ollowing detailed description taken in conjunction with the appended drawings in which:

FIGURE 1 is a perspective view, partly broken away, of a bowling pin embodying my invention,

FIGURES 2 and 3 are sections taken along lines 2-2 and 3--3 respectively in FIGURE 1, andv lFIGURE 4 is a sectional view showing in greater detail the bottom of a bowling pin embodying my invention.

Turning now to the drawings for a more detailed description of a lbowling pin embodying my invention, I have shown a bowling pin 10 which has an upper part 11 and a lower part 12. Parts 11 and 12 are made entirely of plastic and have side walls 13 which define an interior compartment 14.

Interior compartment 14 is divided into a plurality of smaller compartments 14a by divider walls which form a rigid web 15 in each part 11 and 12, web 15 supporting side walls 13.

It will be seen that in the preferred embodiment the divider walls extend parallel to the longitudinal axis of the bowling pin. There are radial divider walls 16a ,and 16h and annular divider walls 17 and 1'8. Annular divider wall 18 is positioned within and is concentric with respect to annular divider wall 17. Radial divider walls 16a are positioned between side walls 13 and annular divider wall 17, while radial divider walls 16b lare positioned between annular ydivider walls 17 and 18. Radial divider walls 16a are secured to side walls 13 and annular divider wall 17, and radial divider walls 16b arev secured to annular divider walls 17 and 18 by virtue of the fact that the whole part 10 4including the rigid web 15 is injection molded as a unit, .as'is the whole part 12.

A metal core member 19 which is preferably a hollow tube made of aluminum and which is ared or flanged at both ends is secured within bowling pin 10, the inner surface 20 of inner annular divider wall 18 firmly contacting the outer surface 21 of tube 19.

Lower part 12 is recessed at 22 and has an annular channel 23 therein. Upper part 11 fits int-o annular chan- .nel 23 as shown, and any suitable means such as a lfast drying resin is used to cement parts 11 and 12 together at 23.

A cap 24 made of a suitable plastic and having a head 25 and a finger 26 is positioned in lower part 12 with finger 26 in tube 19, finger 26 being press fitted into tube 19. Head 25 has a channel 27 which accommodates the anged or flared end of tube 19.

A number of plastics may be used in practising my invention. Preferably an ABS polymer such as Cycolac (trademark), or an ethyl cellulose plastic such as Ethocel (trademark) should be used.

Acrylonitrile-butadiene-styrene (ABS) plastics are characterizednby high impact strength, tensile strength, rigidity and hardness and have a broad range of temperature usefulness. The` chemical resistance property of ABS plastics also is very good. The impact resistance of ABS polymers is outstanding. When impact fractures occur, they lare ductile in nature and not sharp and brittle, mdrcating high energy absorption before rupture. The toughness of ABS polymers is not radically affected by orientation, molded-in strain, moisture content, etc.

Ethyl cellulose moldings are characterized by their toughness over a Wide temperature range, dimensional stability and freedom from odour. Excellent surface lustre ladds greatly to the aesthetic value of articles molded from ethyl cellulose. Ethyl cellulose plastics have a very low density, exceptionally high impact resistance, high heat distortion temperature, high degree of flexibility and good processability.

The provision of rigid web 15 in each part 11 and 12 contributes to the rigidity of bowling pin and assists in the creation of a bowling pin with appropriate actionf Furthermore, the provision of compartments 14a within web 1S assists in the simulation of the sound created by a wooden bowling pin. This sound simulation also is enhanced by the fact that tube 19 is hollow, Slight changes in sound effects and perfect Weight may be achieved by filling compartments 14a with an expanded plastic such as expanded styrene. Pelaspan (trademark) expandable styrene beads may be used, for example.

Tube 19 serves to align upper and lower parts 11 and 12 respectively, holds these parts together, adds strength to the bowling pin, particularly the head thereof, and contributes to simulating the sound of wood.

In manufacturing a bowling pin embodying my invention, upper and lower parts 11 and 12 respectively including webs 15 lare injection molded, upper part 11 being molded about tube 19, so that ange 19a thereof is irn- Abedded in the head 10a of the bowling pin. Compartments 14a in lower part 12 yare filled with'water and expandable plastic pellets. Upper and lower parts 11 and 12 then are assembled, end 19b is fiared as at 19C, and cap 24 is placed in position. Subsequently the assembled bowling pin is passed through a dielectric heating step where the pellets of expandable plastic are expanded. In this manner the bowling pin is further strengthened. Finally a transfer or decal and stripes may be applied to the pin, fand a coat of protective lacquer for the latter applied. It will be appreciated, of course, that a conventional rubber ring 28 will be seated in recess 22. Because of the nature of the manufacturing process, bowling pins so manufactured will be found to have uniform characteristics.

If it should be necessary to resurface bowling pin 10 at any time, this may be done easily by yapplying a coat of plastic to the pin. It will be found that this coat will bond better to the plastic bowling pin than to a wooden bowling pin.

Those skilled in the art will appreciate that, while I have described preferred embodiments of my invention, changes may be made therein without departing from the spirit and scope of my invention as defined in the appended claims.

What I claim as my invention:

1. A bowling pin having plastic side walls, said side walls defining an interior compartment; a plurality of divider walls dividing the interior compartment into a plurality of smaller compartments, said divider walls forming a rigid web supporting said side walls and extending parallel to the longitudinal axis of said bowling pin with at least some of said divider walls extending radially, said divider walls including first and second annular divider Walls in the interior compartment, said second annular divider wall being positioned within and concentric with respect to said first annular divider wall, first ones of said radially extending divider walls extending between said lirst `annular divider wall :and said side walls, second ones of said radially extending divider walls extending between said iirst and second annular divider walls; and a metal core member mounted within said second annular divider wall and secured within said bowling pin, the inner surface of said second annular divider Wall contacting the outer surface of said metal core member.

2. A bowling pin according to claim 1 wherein said metal core member is a hollow tube.

3. A bowling pin according to claim 2 wherein said plastic is selected from the group consisting of acrylonitrile-butadiene-styrene plastic and ethyl cellulose plastic, said bowling pin having at least an upper part and a lower part, said hollow tube joining said parts together and being secured to both said upper part and said lower part.

4. A bowling pin according to claim 3 including an expanded plastic in the interior compartment of said bowling pin.

5. A bowling pin according to claim 1 wherein said metal core member is a hollow aluminum tube.

6. A bowling pin according to claim 1 wherein said plastic is selected from the group consisting of acrylonitrileJbutadiene-styrene plastic and ethyl cellulose plastic.

7. A bowling pin according to claim 1 having at least an upper part and a lower part,-said metal core member joining said parts together.

8. A bowling pin according to claim 7 wherein said metal core member comprises a hollow metal tube positioned within said bowling pin and having at least two projections extending outwardly therefrom, one of said projections engaging said upper part, the other of said Vprojections engaging said lower part, whereby said tube joins said parts together.

9. A bowling pin according to claim 8 including an expanded plastic in the interior compartment of said bowling pin.

10. A bowling pin according to claim 9' wherein said expanded plastic is expanded styrene.

11. A bowling pin according to claim 8 wherein said projections are flanges formed at the ends of said hollow tube, and wherein said lower part has a recess formed in the bottom thereof, said lower part having a shoulder defining the bottom wall of said recess, said other projection engaging said shoulder, and including a cap fitted into said recess and secured therein.

References Cited UNITED STATES PATENTS 1,969,378 8/ 1934 McKenzie 273-82 2,517,116 8/ 1950 Klinger 273-82 2,797,923 7/ 1957 Dettman 273-82 3,037,771 6/ 1962 Gambino.

3,044,777 y7/ 1962 Friedman 273,-82 3,048,400 8/ 1962 Friedman 273-82 3,138,380 6/ 1964 Satchell et al. 273--82 RICHARD C. PINKHA-M, Primary Examiner. 

1. A BOWLING PIN HAVING PLASTIC SIDE WALLS, SAID SIDE WALLS DEFINING AN INTERIOR COMPARTMENT; A PLURALITY OF DIVIDER WALLS DIVIDING THE INTERIOR COMPARTMENT INTO A PLURALITY OF SMALLER COMPARTMENTS, SAID DIVIDER WALLS FORMING A RIGID WEB SUPPORTING SAID SIDE WALLS AND EXTENDING PARALLEL TO THE LONGITUDINAL AXIS OF SAID BOWLING PIN WITH AT LEAST SOME OF SAID DIVIDER WALLS EXTENDING RADIALLY, SAID DIVIDER WALLS INCLUDING FIRST AND SECOND ANNULAR DIVIDER WALLS IN THE INTERIOR COMPARTMENT, SAID SECOND ANNULAR DIVIDER WALL BEING POSITIONED WITHIN AND CONCENTRIC WITH RESPECT TO SAID FIRST ANNULAR DIVIDER WALL, FIRST ONES OF SAID RADIALLY EXTENDING DIVIDER WALLS EXTENDING BETWEEN SAID FIRST ANNULAR DIVIDER WALL AND SAID SIDE WALLS, SECOND ONES OF SAID RADIALLY EXTENDING DIVIDER WALLS EXTENDING BETWEEN SAID FIRST AND SECOND ANNULAR DIVIDER WALLS; AND A METAL CORE MEMBER MOUNTED WITHIN SAID SECOND ANNULAR DIVIDER WALL AND SECURED WITHIN SAID BOWLING PIN, THE INNER SURFACE OF SAID SECOND ANNULAR DIVIDER WALL CONTACTING THE OUTER SURFACE OF SAID METAL CORE MEMBER. 